JP2013215057A - Stator fixing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator fixing structure capable of fixing a stator core stably in the axial direction for preventing a split core from having more hysteresis so as to avoid buckling of the split core.SOLUTION: A stator fixing structure includes: a cylindrical stator core 11; a holding cylinder 1 having a cylindrical body with bottom surfaces 2, 20 at one end in the axial direction, into which the stator core 11 is inserted so that the end surface of one side of the stator core 11 in the axial direction is in contact with the bottom surfaces 2, 20; an annular pressing member 5 having annular contact parts 16, 160 with which the end surface of the other side of the stator core 11 in axial direction is in contact, and fixed to a housing 17 along with the holding cylinder 1, for tightly fastening the stator core 11 in the axial direction; and a slit 10 for splitting the inner peripheral end parts of the contact part 16, 160.

Description

  The present invention relates to a structure for fixing a stator of a rotating electrical machine to a housing.

  Generally, a stator core of a rotating electrical machine is formed by laminating a plurality of divided cores in an annular shape. As a stator core fixing means, a technique is disclosed in which the stator core is press-fitted or shrink-fitted into a holding ring having an inner peripheral diameter substantially the same as the outer peripheral diameter of the annular stator core (see, for example, Patent Document 1). ).

  That is, according to the prior art, the stator core of the rotating electrical machine is pressed in the center direction from the outer peripheral surface thereof, so that the wedge-shaped divided cores constituting the annular stator core are pressed and fixed to each other in the circumferential direction. It is.

JP 2011-250631 A

  However, when the stator core of the rotating electrical machine is fixed by the conventional technique, a compressive stress based on a circumferential pressing force acts on each divided core. Since the direction of the compressive stress coincides with the direction of magnetic flux generation of the stator core, there arises a problem that the hysteresis loss in the stator core increases and the split core made of the electromagnetic steel plate buckles. Further, due to the difference in thermal expansion coefficient between the stator core and the retaining ring, there is a possibility that the clamping force of the split core is insufficient and the fixing of the stator core becomes unstable.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a stator fixing structure capable of stably fixing a stator core in the axial direction.

  The invention according to claim 1, which has been made to achieve the above object, has a cylindrical stator core (11) and a cylindrical shape having a bottom surface (2, 20) at one axial end, and the bottom surface (2, 20) and the holding cylinder (1) into which the stator core (11) is inserted so that the end surface on the one side in the axial direction of the stator core (11) contacts with the end surface on the other side in the axial direction of the stator core (11). An annular pressing member (5) having an annular contact portion (16, 160) in contact therewith and fastened to the housing (17) together with the holding cylinder (1) to axially clamp the stator core (11). ) And a slit (10) provided so as to divide the inner peripheral end of the contact portion (16, 160).

  According to this configuration, the abutting portion (16) of the pressing member (5) that abuts on the end surface of the stator core (11) includes the plurality of slits (10), and thus the axial clamping force of the stator core (11). Can be adjusted according to the circumferential position of the stator core (11), and the stator core (11) can be stably fixed in the axial direction.

It is a front view showing one embodiment of a stator fixing structure of the present invention. It is II-II sectional drawing in FIG. It is a perspective view which decomposes | disassembles and shows the stator fixing structure of this invention. It is sectional drawing which expands the A section of FIG. 2, and shows the holding structure of a stator core. It is sectional drawing which expands the A section of FIG. 2, and shows the other form of the holding structure of a stator core.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, parts corresponding to each other in all the drawings in this specification are denoted by the same reference numerals, and description of the overlapping parts will be omitted as appropriate.

  The stator of the rotating electrical machine of the present embodiment is a cylindrical body formed by winding a coil (not shown) in the slot 13 of the stator core 11. The stator core 11 is inserted into the holding cylinder 1, and one end face thereof is in contact with the bottom surfaces 2 and 20 of the holding cylinder 1. The other end surface of the stator core 11 abuts against a holding member 5 that covers the holding cylinder 1 that houses the stator core 11.

  The holding cylinder 1 and the pressing member 5 are fastened to the housing 17 with bolts 9 in a state where the respective mounting holes 8 are continuously formed. At this time, as shown in FIGS. 4 and 5, the axial dimension of the stator core 11 and the holding cylinder 1 so that a slight gap G is formed between the flange 7 of the holding cylinder 1 and the flange 7 of the pressing member 5. The depth dimension is set. Therefore, an axial pressing force is applied to the stator core 11 by the tightening force of the bolt 9. With this configuration, the stator core 11 is fixed to the housing 17. Further, the housing 17 supports a cylindrical rotor (not shown) that rotates close to the inner wall of the central hole of the stator core 11 on the central axis of the stator core 11.

  The holding cylinder 1 is a cylindrical body having a plurality of flanges 7 having bottom surfaces 2 and 20 and an opening 3 at one end in the axial direction and mounting holes 8 at the other end. A stepped portion 4 having an enlarged diameter is formed in a cylindrical portion near the other end of the holding tube 1.

  The stator core 11 is formed by laminating a plurality of divided cores 12 made of electromagnetic steel plates or powder iron cores in an annular shape. Since the stator core 11 has a diameter set so that it can be inserted into the inner peripheral portion of the holding cylinder 1 excluding the stepped portion 4, the end surface of the stator core 11 can come into contact with the bottom surfaces 2 and 20 of the holding cylinder 1.

  The holding member 5 includes an annular plate having an inner diameter that is an intermediate dimension between the diameter of the stator core 11 and the valley diameter of the slot 13 and an outer diameter that is substantially equal to the diameter of the holding cylinder 1. On the outer periphery of the annular plate of the pressing member 5, a plurality of flanges 7 project in the radial direction. An attachment hole 8 is drilled in the flange 7 so as to be continuous with the attachment hole 8 of the holding cylinder 1. A cylindrical portion 6 having an inner diameter slightly larger than the outer diameter of the stator core 11 and an outer diameter slightly smaller than the inner diameter of the stepped portion 4 of the holding cylinder 1 is concentric with the annular plate. Is erected. When the cylindrical portion 6 is inserted into the stepped portion 4 of the holding cylinder 1 and the flanges 7 of the cylindrical portion 6 and the holding tube 1 are brought into contact with each other, the front end surface of the cylindrical portion 6 comes into contact with the stepped surface of the stepped portion 4. The height dimension of the cylindrical part 6 and the width dimension of the step part 4 are set so that it may not. The surfaces of the annular plate on the side where the cylindrical portion 6 is erected and from the inner periphery to the inner diameter side of the cylindrical portion 6 are annular contact portions 16 and 160 with which the end surface of the stator core 11 contacts.

  In the contact portions 16 and 160 of the pressing member 5, slits 10 are engraved on the circumference at equal intervals so as to divide the inner peripheral ends of the contact portions 16 and 160. The slit 10 is provided so as to correspond to a position where the split cores 12 abut on each other in the circumferential direction. The shape of the slit 10 is illustrated as a bowl shape, but may be any shape as long as the pressing pieces 18 formed between the slits 10 can be individually displaced. The pressing piece 18 can press the end face of each divided core 12 with a force that changes according to the individual height. Thus, it is preferable to provide each slit 10 so that one pressing piece 18 corresponds to one divided core 12. However, a slit may be provided so that one pressing piece presses the plurality of divided cores. Further, the number of divided cores pressed by one pressing piece may be constant or may be arbitrarily changed.

FIG. 4 shows the holding structure of the stator core 11 by enlarging the part A of FIG.
The axial cross section of the stator core 11 has a trapezoidal shape, and the bottom surface 2 and the contact portion 16 that press the taper surfaces 14 and 15 respectively have the same taper angle as the taper surfaces 14 and 15. The taper of both the tapered surfaces 14 and 15 is an angle such that the upper base of the trapezoidal shape corresponding to the valley of the slot 13 is on the center axis side of the stator core 11. That is, the tapered surface 14 and the tapered surface 15 that are recessed in the shape of a mortar are pressed by the bottom surface 2 and the contact portion 16 having the same taper angle as the respective surfaces, so that the stator core 11 is externally indicated by an outward arrow. A direction force acts. Since this outward force opposes the magnetic attraction force of the rotor (not shown), the cylindricity of the stator core 11 is improved and the fixing force of the stator core 11 is improved.

FIG. 5 shows another form of the holding structure of the stator core 110 in an enlarged view of the portion A in FIG.
The axial cross section of the stator core 110 has a trapezoidal shape, and the bottom surface 20 and the contact portion 160 that press the taper surfaces 140 and 150 respectively have the same taper angle as the taper surfaces 140 and 150. The taper of both tapered surfaces 140 and 150 is an angle such that the lower base of the trapezoidal shape corresponding to the valley of the slot 13 is on the center axis side of the stator core 110. That is, the tapered surface 140 and the tapered surface 150 protruding in the shape of a truncated cone are pressed by the bottom surface 20 and the contact portion 160 having the same taper angle as each surface, and therefore, the stator core 110 is indicated by an inward arrow. Inward force acts. This inward force presses the divided cores 12 in the circumferential direction to improve the mutual adhesion between the divided cores 12, thereby reducing the magnetic resistance of the magnetic path and contributing to improving the efficiency of the rotating electrical machine. The direction of the inward force is the same direction as the radial pressing force of the stator core in the prior art. However, the inward force is concentrated on both ends of the stator core 110 in the axial direction, hardly exists in the central portion, and is generated as a component force due to a relatively small taper angle of the axial pressing force. Therefore, the inward force is different from the pressing force of the prior art.

As is clear from the above detailed description, according to the stator fixing structure of the present embodiment, the stator has a cylindrical stator core 11 and a cylindrical shape having bottom surfaces 2 and 20 at one end in the axial direction. 20, a holding cylinder 1 into which the stator core 11 is inserted so that one end surface in the axial direction of the stator core 11 contacts, and an annular contact portion 16 in which the other end surface in the axial direction of the stator core 11 contacts. An annular holding member 5 which is fastened to the housing 17 together with the holding cylinder 1 and presses the stator core 11 in the axial direction, and the inner peripheral ends of the contact portions 16 and 160 are divided. And a slit 10 provided on the surface. Therefore, the axial pressing force of the stator core 11 can be adjusted according to the circumferential position of the stator core 11, and the stator core 11 can be stably fixed in the axial direction.
Further, the stator core 11 is formed by laminating the divided cores 12 in an annular shape, and the slit 10 is provided at a position corresponding to the contact surface between the divided cores 12. As a result, the stator core 11 can be stably fixed.
Further, the axial cross section of the stator core 11 has a trapezoidal shape, and the bottom surface 2 and the abutting portion 16 of the holding cylinder 1 that press the both tapered surfaces 14 and 15 respectively have the same taper as the both tapered surfaces 14 and 15. The taper of both the tapered surfaces 14 and 15 is such that the upper base of the trapezoidal shape is on the central axis side of the stator core 11. Therefore, the outward force acting on the stator core 11 has an excellent effect of improving the cylindricity of the stator core 11 and improving the fixing force of the stator core 11.
In addition, the axial cross section of the stator core 110 has a trapezoidal shape, and the bottom surface 20 and the contact portion 160 of the holding cylinder 1 that press the both tapered surfaces 140 and 150 respectively have the same taper as the both tapered surfaces 140 and 150. The taper of both the tapered surfaces 140 and 150 is an angle such that the lower base of the trapezoidal shape is on the center axis side of the stator core 110. Therefore, the inward force acting on the stator core 110 presses the divided cores 12 in the circumferential direction to improve the mutual adhesion between the divided cores 12, thereby reducing the magnetic resistance of the magnetic path and improving the efficiency of the rotating electrical machine. Has an excellent effect of.
In addition, since the pressing member 5 includes the cylindrical portion 6, the rigidity of the pressing member 5 is improved, and an excellent effect is obtained that variation in the fastening force of the stator core 11 is reduced.

  In addition, this invention includes what can be implemented in the aspect which added various change, correction, improvement, etc. based on the knowledge of those skilled in the art. Further, it goes without saying that any of the embodiments to which the above-mentioned changes are added is included in the scope of the present invention without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Holding cylinder 2, 20 Bottom surface 5 Holding member 10 Slit 11 Stator core 12 Divided core 16, 160 Contact part 17 Housing

Claims (6)

A cylindrical stator core (11);
The stator core (11) has a cylindrical shape with a bottom surface (2, 20) at one end in the axial direction, and the stator core (11) is located inside such that the end surface on one side in the axial direction of the stator core (11) contacts the bottom surface (2, 20). A holding cylinder (1) to be inserted;
The stator core (11) has an annular contact portion (16, 160) with which the other end surface in the axial direction abuts, and is fastened to the housing (17) together with the holding cylinder (1) to attach the stator core (11). An annular holding member (5) that is axially clamped;
A slit (10) provided to divide the inner peripheral end of the contact portion (16, 160);
A stator fixing structure comprising:   The stator core (11) is formed by laminating divided cores (12) in an annular shape, and the slit (10) is provided at a position corresponding to a contact surface between the divided cores (12). The stator fixing structure according to claim 1.   The axial cross section of the stator core (11) has a trapezoidal shape, and the bottom surface (2, 20) and the abutment of the holding cylinder (1) that respectively press both tapered surfaces (14, 140, 15, 150) thereof. 3. The stator fixing structure according to claim 1, wherein the portions (16, 160) have the same taper angle as both the tapered surfaces (14, 140, 15, 150). 4.   4. The stator fixing according to claim 3, wherein the taper of both the tapered surfaces (14, 15) is an angle such that the upper base of the trapezoidal shape is on the central axis side of the stator core (11). Construction.   4. The stator fixing according to claim 3, wherein the taper of both the tapered surfaces (140, 150) is an angle such that a lower bottom of the trapezoidal shape is on a central axis side of the stator core (11). Construction.   The stator fixing structure according to any one of claims 1 to 5, wherein the pressing member (5) includes a cylindrical portion (6).

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